The testing was conducted by Infineum International LTD, a major global additive company. It involved two 2008 Peterbilt sleeper tractors in long-haul, fully loaded service, with each rig traveling one million miles using only the EcoPower engine oil. The trucks' engines, 2007 Cummins ISX 450-horsepower EGR models, were subjected to oil-drain intervals of 40,000 to 50,000 miles, compared to the manufacturer-recommended 25,000 miles.

The engines were mated to Eaton Fuller 10-speed manual transmissions.

At each drain interval, the oil was analyzed for the presence of wear metals, a sign of engine wear; acid neutralization, as reflected in a calculation known as total base number (TBN); and viscosity maintenance, an important indicator of the oil's ability to prevent corrosion and provide engine protection.

Oil analysis found that the EcoPower Heavy-Duty Diesel 15W-40 CJ-4/SM maintained a TBN of 4.9 - "well within limits and showed a substantial ability to neutralize harmful acids that build up in used engine oil and cause corrosion," said Rodney Walker, Safety-Kleen's technical director of oil re-refining. "There were also completely acceptable levels of wear metals, and just like in previous tests, EcoPower was proven to maintain its viscosity, even at the end of each oil-change cycle. Viscosity maintenance is critical to oil protecting an engine, and illustrates EcoPower's exceptional protective properties."

EcoPower is re-refined using a process that consumes up to 85 percent less energy than refining engine oil from crude oil, notes Curt Knapp, senior vice president and chief marketing officer for Safety-Kleen, the largest collector and re-refiner of used oil in North America. Fleets using the oil can protect engines while protecting the environment by reducing greenhouse gas emissions.